Sound-proofing component

ABSTRACT

A component for sound proofing internal combustion engines having two frame members attached to the surface of the engine and arranged in spaced relation to the engine and spaced from each other with sound proofing packing between the frame members.

United States Patent [15 3,695,386 Thien et al. 1 51 Oct. 3, 1972 [54]SOUND-PROOFING COMPONENT 3,464,398 9/ I969 Scheiterlein et al.. I 8 H33K X 72 Inventors: Gerhard Thien; H in F hbach 3,521,726 7/1970 Freyn .18V33 K both of Oral, Austri; ac 3,530.840 9/1970 Freyn 181/33 K xAssignee? Hans List Gral, Austria Primary Examiner-Richard B. Wilkinson2 Filed; Mal-ch 18, 1970 Assistant Examiner--John F. GonzalesAttorney-Watson, Cole, Grindle & Watson 211 Appl. No.: 20,758

[57] ABSTRACT [30] Fm'eign Appficafio Priority Dam A component for soundproofing internal combustion March 20, 1969 Austria ..A 2802/69 engineshaving two frame members mached the surface of the engine and arrangedin spaced relation 52 us. 01. ..l8l/33 K, 123/195 0 to the engine andspaced from each Other with sound 5 1 1m. (:1. .102: 7/00, Fl6m 1/00,GlOk 11/00 Proofing packins'between the frame members- [58] Field ofSearch ..l8l/33 K,'33 A, 33 G, 33 R, 123/195 (3,198 E, 52 MC, 41.70,41.07

[56] References Cited 5 Claims, 7 Drawing Figures UNITED STATES PATENTS3,540,425 1 l/ 1970 Scheiterlein et al..'l8 ll33 K X PATENIEDHBIS m23.695.386

sum 2 or 2 1 SOUND-PROOFING- COMPONENT The invention relates to asound-proofing component for the sheathing of machines, particularly ofinternal combustion engines.

Efforts to control excessive engine noise have been responsible for thedevelopment of a number of more or less effective components for theprincipal purpose of screening the machine off sound radiationsemanating from the outer walls of the machine. However, similarcomponents of conventional design present certain shortcomings both withregard to their installation and operation, in addition to beinggenerally responsible for a considerable increase of the weight of themachine.

Particularly in an internal combustion engine of a known design, thecylinder block, as different from conventional casting types, is formedby a framework made of steel plates and covered on both sides and in thearea of thecrankcase by sound-proofing multilayer plates called sandwichmetal sheets. in their plainest form these sound-proofing elementsconsist of two massive steel plates arranged in spaced relation to eachother, and interconnected by means of an interposed layer ofsound-proofing material in such a manner that the inside steel plateonly is screwed onto the crankshaft housing with the interposition ofpacking strips-However, this type of sound-proofing is highlyobjectionable insofar as it strongly impairs the abduction of heat fromthe cylinder block towards its surroundings, inasmuch as in view of itslow thermal conductively the sound-absorbing material also acts in aheat-insulating capacity. This leads to an objectionable rise of the oiltemperature which will have to be compensated by appropriate measuressuch as for example, the provision of a large-sized oil cooler.

It is therefore, the object of the present invention to provide aneasily installable and adaptable component for the sound-proof sheathingof machines avoiding the shortcomings of known devices. According to theinvention such a component is characterized by a first frame memberrigidly attached to the outside of the machine and by a second framemember arranged in spaced relation to and in front of, the first andconnected with the same by means of a sound-proofing packing along acontinuous series of lines, the said second frame member covering atleast part of the outer surface of the machine and/or serving as asupport for one or several encasements.

l'ixperienee goes to show that such a component of plain design presentssound-proofing properties of a surprisingly high degree despite thedeliberate omission of sound-absorbing intermediate layers, withoutimpairing the exchange of heat between the machine and its surroundings.

The framework construction of the component according to the inventionoffers not only the advantage of its low weight, but in addition thepossibility of providing a component of appropriate rigidity to be usedalso as a supporting element. Furthermore, where the external secondframe member is so designed as to serve as a support for encasements, itwill be possible for such elements as are directly associated with themachine, such as the oil sump of an internal combustion engine forexample, to be attached to the said second frame member as encasements.This further simplifies the overall design of the machine andadditionally-helps reduce its weight.

According to a preferred embodiment of the invention, one of the twoframe members is designed as a closed, possibly arched plate and/orreinforced by means of corrugations. This design is particularlysuitable for the sound-proofing encasement of large surfaces of themachine. Where a very tight connection between the component and itsmounting surfaces on the machine is required, it will be preferable toattach the component with its plate-shaped rim rigidly to the machineand to provide an additional sealing between the plate and its mountingsurfaces on the housing, such as by means of a sealing compound ofprofile washers.

According to another embodiment of the invention at least one of the twoframe members can be designed at least one of the two frame members canbe designed as a strip having a mounting rim protruding from the packingeither on one side or both. The encasements provided can be attached tothe mounting rim in any convenient manner such as by screwing, gluing orrivetting. lf desirable in view of the particular shape of theencasements to be mounted, it is also possible for the mounting rim ofthe strip-shaped frame member to be of angular-shaped or of any'otherconvenient form.

According to a further feature of the invention the strip-shaped framemember can be attached alongside its mounting rim to the rim of aconnecting plate provided on the outer surface of the machine bywelding, gluing, flanging or the like. in that case, the additionalconnecting plate provides positive sealing of the encased machinecompartment against the outside. The encasements mounted on the secondsound-proofing frame member or the external frame member designed as aplate are exclusively used for sound-proofing purposes. The distancebetween the additional connecting plate and the sound-proofing plate infront of it is of particular importance for the sound-proofing capacityof the component according to the invention. The most convenientdistance should be determined by trial and error.

According to a further embodiment of the invention the packing made ofrubber, synthetic material or the like is attached to the two framemembers by vulcanization or gluing. In particular, attachment byvulcanization is feasible only in connection with a component accordingto the invention, since at least one of its frame members is open-workedso that the packing can be easily heated to the required uniformvulcanization temperature.

In some cases it will be preferable to provide an additional support forthe second frame member or for an encasement attached thereto by meansof at least one sound-proofing supporting element mounted on the outersurface of the machine or on the first frame member. This helpseliminate objectionable vibrations particularly where large-sizedencasements are used. The provision of additional supporting elementsmay, however, prove useful also for considerations of a mechanicalnature.

Further details of the invention will appear from the followingdescription of several embodiments of the invention with reference tothe accompanying drawing in which FIG. 1 shows a diagrammaticcross-sectional viewof the cylinder block of an internal combustionengine encased by means of sound-proofing components according to theinvention,

FIG. 2 illustrates a detail of FIG. 1 on a larger scale, and

FIGS. 3 to 5 are cross-sectional view of various types of sound-proofingcomponents according to the invention,

FIG. 6 is a diagrammatic cross-sectional view of yet another embodimentof the invention, and

FIG. 7 is a cross-sectional view on line VII-VII of FIG. 6.

As shown in FIG. 1, the housing 1 of an internal combustion engine isprovided with a sound-proofing sheathing substantially comprising twosound-proofing components 4 and 5 spaced in front of the two side walls2 and 3 of the housing 1, and a further soundproofing component 6arranged on the lower rim of the housing 1 and to which the oil sump 7is attached.

The essentially identical components 4 and 5 comprise a firstframe'member l rigidly mounted on the housing 1 by means of bolts 8 withthe interposition of a continuous profile washer 9 and connected to aplateshaped second frame member 11 by means of a continuous elasticpacking 12 in such a manner as to provide effective sound isolation. Thepacking 12 made of rubber for example, extends alongside thefirst-mentioned frame member 10 and is positively and tightly attachedthereto and also to the plate-shaped frame member 1 by vulcanization orgluing. The plate-shaped frame member 11 is reinforced by means ofhorizontal and vertical corrugations 13 and 14.

At the points of attachment of the sound-proofing components 4 and onthe housing 1, the frame member and the packing 12 are somewhat enlargedfor receiving the bolts 8. The bolts 8 are countersunk in a steppedthrough bore 15 and rest with the interposition of a circlip 16 upon theannular shoulder formed by the bore 15 on the inner frame member 10.

The component 6 mounted on the underside of the housing I also comprisestwo frame members 10' and 11' interconnected by means of asound-proofing elastic packing 12' and screwed to the lower rim of thehousing 1 with the interposition of a continuous profile washer 9'. Thestrip forming the outer frame member 11 presents a mounting rimprotruding inwardly from the packing 12', the upper rim 17 of the oilsump 7 being attached to the said mounting rim by means of an oiltightflange 18. Thus the coil sump 7 forms a soundproofing encasementattached to the housing 1 and serving to screen off sound radiation fromthe housing I downwards.

The oiltight and substantially bend-resisting design of thesound-proofing components 4 and 5 makes is possible for the sidewalls 2and 3 of the housing 1 to be provided with large-area recesses in such amanner that the components 4 and 5 themselves form the oil-wetted outerwalls of the housing 1. This eliminates the need for providingdouble-walled outer surfaces of the housing and helps save much weight.Likewise, the front walls of the housing I could be sheathed by means ofsound-proofing components of a similar design in such a manner as toinhibit heat radiation from the machine on all sides.

FIG. 3 shows a particularly plain type of component designed accordingto the invention. The inner frame member 20 directly adjoining the body19 of the machine to be sound-proofed is designed as through plate andthe second frame member 21 connected therewith by means of asound-proofing elastic packing 22 as a strip with an inwardly protrudingmounting rim. Alongside this rim a plate-shaped encasement 23 ispositively connected with the frame member 21 in any convenient mannersuch as by gluing the members 21 and 23 (right side of FIG. 3) or bymeans of rivets 24- (left side of FIG. 3).

According to the embodiment of the invention illustrated in FIG. 4,thetwo frame members 20 and 21 of the sound-proofing component aredesigned as strips having a laterally protruding mounting rim, aseparate connecting plate 25 directly adjoining the machine body 19presenting a laterally protruding rim to which the inner frame member20' of the sound-proofing component is attached. The members 20 and 25can be interconnected by any convenient method, such as for example bywelding (right side of FIG. 4) or by fianging (left side of FIG. 4). Anencasement 26 forming a salient bonnet is attached to the mounting rimof the outer frame member 21 by means of rivets 27 (right side of FIG.4) or self-tapping screws 28 (left side of FIG. 4).

The component shown in FIG. 5 comprises a stripshaped inner frame member20" and a plateshaped outer frame member 21' connected therewith bymeans of a sound-proofing elastic packing 22. This design also uses aseparate connecting plate 25' directly adjoining the machine body 19.The plate 25' can either by mounted on the machine body 19 jointly withthe frame member 20" by means of bolts 8 (right side of FIG. 5) or elsethe members 25' and 20" are interconnected by flanging at the rim (leftside of FIG. 5). a

FIG. 6 illustrates the sound-proofing connection of an oil sump 29 tothe lower rim of the housing 1' of an internal combustion engine (notshown). The oil sump is mounted thereon by means of a sound-proofing component 6' comprising a first frame member 30 designed as a sectionalstrip and a second strip-shaped frame member 32, interconnected by meansof a soundproofing elastic packing 32. The component 6' is mounted onthe housing 1 by means of bolts 8 with the interposition of a profilewasher 33. The frame member 31 has an inwardly protruding mounting rimto which the inwardly bent upper rim 42 of the oil sump 29 is attachedby welding.

The oil sump 29 rests upon the housing 1 of the machine supported by anadditional supporting element 34 in such a manner as to provide positivesoundproofing. The supporting element 34 comprises a stay bolt 35screwed into the housing 1' and carrying a covering hood 36, an adjacenttubular sleeve 37, a washer 38 and a nut 39. Shrunk on the sleeve 37 isan elastic bushing 40 made of sound-proofing material such as rubber,and preferably positively connected with the sleeve 37 by vulcanizationor gluing. The elastic bushing 40 protrudes into a bell-shaped recess 41of the oil sump 29 and rests on the open-worked bottom of same. Thebushing 40 can be mounted in the recess 41 also by vulcanization orgluing. The addiv tional supporting element 34 carries part of theweight of the oil sump 29 and at the same time serves to suppress anyoperational vibrations of the oil sump.

We claim:

1. A component for the soundproof sheathing of internal combustionengines, comprising a first frame member rigidly attached to an outersurface of the internal combustion engine, a second frame membercovering at least part of the said outer surface and arranged in spacedrelation to and in front of the said first frame member, a soundproofingpacking located between the said two frame members and tightly connectedwith same along a continuous series of lines, at

least one of the said frame members being a strip having a mounting rimlaterally protruding from the said packing.

2. A component according to claim 1, comprising a connecting platemounted on the outer surface of the internal combustion engine, the saidstrip-shaped frame member being rigidly connected with the outer rim ofthe said connecting plate along its mounting rim.

3. A component according to claim 2, wherein the said rims of the stripand of the connecting plate are interconnected by welding.

4. A component according to claim 2, wherein the said rims of the stripand of the connecting plate are interconnected by gluing.

5. A component according to claim 2, wherein the said rims of the stripand of the connecting plate are interconnected by flanging.

1. A component for the soundproof sheathing of internal combustion engines, comprising a first frame member rigidly attached to an outer surface of the internal combustion engine, a second frame member covering at least part of the said outer surface and arranged in spaced relation to and in front of the said first frame member, a soundproofing packing located between the said two frame members and tightly connected with same along a continuous series of lines, at least one of the said frame members being a strip having a mounting rim laterally protruding from the said packing.
 2. A component according to claim 1, comprising a connecting plate mounted on the outer surface of the internal combustion engine, the said strip-shaped frame member being rigidly connected with the outer rim of the said connecting plate along its mounting rim.
 3. A component according to claim 2, wherein the said rims of the strip and of the connecting plate are interconnected by welding.
 4. A component according to claim 2, wherein the said rims of the strip and of the connecting plate are interconnected by gluing.
 5. A component according to claim 2, wherein the said rims of the strip and of the connecting plate are interconnected by flanging. 